The passage of Proposition 64 not only legalized the use of recreational marijuana, it also sets aside much needed money for research into the drug's effects.

Starting in 2018, Californians 21 and over will be able to buy and use pot without having to get a medical prescription. But this has public health researchers wondering what the impacts will be on individuals and society.

Will auto accidents increase? How about psychiatric disorders? Will more teens start using pot illegally?

To answer those and other questions, the measure allots $12 million a year for research. The money will come from taxes on the drug.

Right now, pot is still considered under federal law as Schedule I narcotic, which means the federal government deems it as dangerous as heroin or LSD.

That's made it hard to get samples for study, and labs looking to do this kind of research need to wade through a lot of red tape. UC San Diego’s Center for Medicinal Cannabis Research has been doing that since 2000.

Igor Grant with the Center said at least $2 million of Prop 64 tax money will go to his group. They’ll look at ways to develop marijuana sobriety tests for drivers. One possible method is to have them track an object with their finger on a screen.

"Maybe can we use an iPad or some kind of tablet device and have somebody do a quick test that more accurately simulates the demands of driving ," he said.

Grant said his team would also like to find a way to tell how high someone is by testing their breath or saliva.

The other $10 million in research money will go to institutions looking to study the societal and health impacts of marijuana use. In particular, the measure spells out the need for research looking at "impacts on public health, including costs associated with marijuana use, as well as whether marijuana use is associated with an increase or decrease in the use of alcohol or other drugs."

It also calls for studies examining how labeling and advertising may affect underage consumption.

"I think it will not be enough," Grant said about the amount of money set aside. Since marijuana research has been so difficult to conduct, there hasn't been a lot of research into its broader impacts.

Still, Grant said the $12 million a year is a good start. He thinks as more people use recreational weed in California, the state government may see the need to put even more money toward this growing field of study.